Credit

Caption

Green alga. Differential interference contrast micrograph of the desmid green alga Micrasterias denticulata . Desmids are a common group of freshwater single-celled algae that have intricate cell walls. Micrasterias are placoderm desmids, which have the cell wall divided into two symmetrical halves, joined by a thin central region called the isthmus. Micrasterias is highly adapted to nutrient poor, acidic water. Magnification: x125 when printed at 10 centimetres wide.